Wyoming is about 1.5 times smaller than Japan.

Japan is approximately 377,915 sq km, while Wyoming is approximately 251,489 sq km, making Wyoming 66.55% the size of Japan. Meanwhile, the population of Japan is ~124.2 million people (123.7 million fewer people live in Wyoming).
Tip: This to-scale comparison of Japan vs. Wyoming uses the Mercator projection, which distorts the size of regions near the poles.
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